Given below are two statements:
Statement I: The period number in the long form of the periodic table is equal to magnetic quantum number of any element of the period.
Statement II: The period number in the long form of the periodic table is equal to maximum principal quantum number of any element of the period.
In the light of the above statements, choose the correct answer from the options given below:

Correct option is D

The Correct answer is(d) Statement I is false but Statement II is true.
Explanation:
• The period number in the periodic table corresponds to the maximum principal quantum number (n) of the elements in that period.
• For example, elements in Period 2 (like Lithium, Beryllium, etc.) have their valence electrons in the second principal shell, meaning their maximum n is 2.
• The magnetic quantum number (ml) describes the orientation of an orbital in space and can have values from minus l to plus l, including zero. It is not directly equal to the period number.
• Therefore, Statement I is false, and Statement II is true.
Information Booster:
• The principal quantum number (n) indicates the main energy level or shell and determines the size and energy of the orbital.
• The azimuthal quantum number (l) defines the shape of the orbital (s, p, d, f).
• The spin quantum number (ms) indicates the spin direction of the electron (plus 1/2 or minus 1/2).
• No two electrons in an atom can have the same set of four quantum numbers (Pauli Exclusion Principle).
• The modern periodic table is arranged by increasing atomic number.